1. Field of the Invention
The present invention relates to particles which are useful as a carrier and a catalyst component for olefin polymerization, a catalyst for olefin polymerization using the same, and method of producing an olefin polymer with said catalyst for olefin polymerization.
2. Description of the Related Arts
Many methods of producing an olefin polymer using a transition metal compound have already been reported. As the example of using a metallocene transition metal compound, for example, Japanese Patent Publication(Kokai) No.58-19309 discloses a method for producing an olefin polymer using bis(cyclopentadienyl)zirconium dichloride and methylaluminoxane as a catalyst.
Since the catalyst using these transition metal compounds is soluble in a reaction system, when used in a polymerization accompanying formation of polymer particles (e.g. slurry polymerization, gas phase polymerization), the shape of the formed polymer particles is irregular, which can cause the formation of a large particle polymer, an agglomerate polymer, a fine powdered polymer and the like, a decrease in the bulk density of the polymer, and adhesion of the polymer to the wall of the polymerization reactor. consequently, these occurrences can cause poor heat transfer and poor cooling in the reactor, which results in difficulty in stable operation and a lowering of productivity.
In order to apply the transition metal compound to the polymerization accompanying formation of polymer particles, it is required that not only that a sufficient polymerization activity is exhibited but also that a polymer excellent in shape and particle properties is obtained. To solve these problems, a method of supporting a transition metal compound on a carrier or the like has been proposed.
For example, a method of fixing or supporting all or a part of catalyst components such as a metallocene complex, methylaluminoxane or the like on an inorganic metal oxide carrier such as silica or the like has been proposed.
For example, in U.S. Pat. Nos. 4,937,299, 5,324,800 or 4,935,474, it is disclosed that a soluble metallocene compound is deposited or adhered on a typical support(e.g. silica, alumina, polyethylene) to convert into a supported heterogeneous catalyst component, and the catalyst component is used as a combination with an aluminoxane in the slurry polymerization or gas phase polymerization.
In Japanese Patent Publication (Kokai) No.61-108610, it is disclosed that an olefin polymer is produced by using a solid catalyst component obtained by adding a calcined silica to a mixture of bis(cyclopentadienyl)zirconium dichloride and a reaction product of trimethylaluminum with water.
In Japanese Patent Publication (Kokai) No.61-276805, it is disclosed that an olefin polymer is produced by using an inorganic oxide-containing organoaluminum component, obtained by reacting a mixture of methylaluminoxane and trimethylaluminum with silica, and bis(cyclopentadienyl)zirconium dichloride.
In U.S. Pat. No. 4,808,561, it is disclosed that an olefin polymer is produced by using a solid catalyst containing aluminum and zirconium, obtained by treating silica in turn with methylaluminoxane and bis(cyclopentadienyl)zirconium chloride.
As improved methods, for example, there has been reported a method of using a solid catalyst component, obtained by fixing or supporting all or a part of a catalyst component such as ametallocene complex, methylaluminoxane, etc. on an inorganic metal oxide carrier such as silica, etc., and aluminoxane or organoaluminum, and a method of using a prepolymerized catalyst obtained by conducting prepolymerization.
Japanese Patent Publication (Kokai) No.63-51407 discloses a method of producing an olefin polymer using a solid catalyst component obtained by treating silica in turn with methylaluminoxane and bis(cyclopentadienyl)zirconium dichloride, and methylaluminoxane.
U.S. Pat. No. 5,700,749 discloses a method of producing an olefin polymer using a solid catalyst component, obtained by treating silica in turn with methylaluminoxane and bis(cyclopentadienyl)zirconium dichloride, and triisobutylaluminum or a method of producing an olefin polymer using a solid catalyst component prepolymerized with the solid catalyst component and triisobutylaluminum.
In the above prior arts, use of aluminoxane is essential. This aluminoxane must be separately synthesized, and the synthesis method is complicated because it requires a lot of steps. The aluminoxane is unstable and costly. Regarding the solid catalyst component obtained by combining the aluminoxane with an inorganic metal oxide carrier such as silica, the amount of aluminum used is large and the activity per 1 mol of an Al atom was low.
To solve these problems, there has been reported a method of producing an olefin polymer using a solid catalyst component obtained by reacting an organoaluminum with water in the presence of an inorganic metal oxide carrier such as silica to form aluminoxane.
For example, Japanese Patent Publication (Kokai) No. 61-31404 discloses a method of producing an olefin polymer using a catalyst obtained by adding water, trimethylaluminum and bis(cyclopentadienyl)zirconium dichloride in turn to silica.
U.S. Pat. No. 4,912,075 discloses a method of producing an olefin polymer using silica gel powders containing a supported metallocene-methylaluminoxane catalyst complex, obtained by adding silica gel not dehydrated, containing water to trimethylaluminum and then treating the resultant with bis(n-butylcyclopentadienyl)zirconium dichloride.
U.S. Pat. No. 5,234,878 discloses a method of producing an olefin polymer using a prepolymerized solid catalyst obtained by adding water, trimethylaluminum and bis(methylcyclopentadienyl)zirconium dichloride in turn to silica and further adding ethylene to the mixture, and triisobutylaluminum.
Further, there was recently reported an example using a clay mineral as a water containing-carrier. In Japanese Patent Publication (Kokai) No.5-295022, there is disclosed a method comprising treating bis(cyclopentadienyl)zirconium dichloride and montmorillinite as a clay mineral with trimethylaluminum, further adding ethylene to obtain a prepolymerized solid catalyst, and producing a olefin polymer using the solid catalyst.
These prior art references describe that synthesis of an aluminoxane, and at the same time, fixing of the aluminoxane to an inorganic metal oxide carrier such as silica can be easily performed by a simple method. However, solid catalyst components obtained by this method have a low activity unlike a solid catalyst component obtained by fixing the separately synthesized aluminoxane, and the particle properties of the resulting polymer are not preferred.
Recently, there has been reported a method of preparing an olefin polymerization catalyst using an aluminum compound wherein a special group is introduced, in place of an aluminoxane, in combination with a transition metal compound, or in combination with an additional organoaluminum compound, and a method producing an olefin polymer with said catalyst.
For example, Japanese Patent Publication (Kokai) No.6-329713 discloses a method of producing an olefin polymer using a solid component of an aluminum compound having an electron attractive group, obtained by reacting trimethylaluminum and pentafluorophenol, and bis(cyclopentadienyl)titanium dichloride. There is also described a method of producing a catalyst component by supporting an aluminum compound, wherein a special group is introduced, on an inorganic carrier or an organic carrier. However, there is not disclosed an example of actually supporting an aluminum compound having an electron attractive group obtained by reacting trimethylaluminum with pentafluorophenol, and the polymerization activity in case of using a supported solid catalyst component as described in the above-prior art reference was low.